Sculpting and Retopology

Week 5

We started with a brief exercise of creating a silhouette before we proceeded to Zbrush. This exercise was meant to help us understand the basic shapes that make a character. 

Before assigning another exercise, our professor gave us a rundown of Zbrush and its hotkeys and interface. We were to sculpt lips by ourselves on any available human head models from the asset library in Zbrush. First, I started by collecting reference images and putting them together using PureRef, great software to keep your pictures organised. You can choose and select the picture you like and simply drag and drop them into it.

Because the interface was still relatively new, I decided to refer to a tutorial and follow it. The tutorial helped break down the available brush tools and the entire process in a few minutes. After getting more familiar with the brushes and the basic hotkeys, I tried sculpting the lips.

For the second half of the class, to help us understand sculpting better, we watched a tutorial on human anatomy and what each part was named and looked like. When it comes to sculpting, it is advisable to follow the human anatomy to get that realistic look. This helps with getting the right look and dimensions in the real world.

Week 6

Week 6 started off with Retopology in Autodesk Maya

Retopology is nothing but just simplifying the complex geometry in a topology of a mesh as a way to lower the poly count and make it cleaner. This helps a lot, especially when you want to rig a 3d model but other than that, with retopology, 3d sculpted and modelled objects can be cleaned and made ready for UV unwrapping and sculpting. 

Above are some good examples of how to start with a good retopology. It is very important to have a good retopology because just reducing the polygons won't do the job. It should also make sure the silhouette of the model remains unchanged. If done right, it can provide a base for baking. 

To start, it is advisable to target denser areas first which have more edge flows but also to make sure, the overall shape and silhouette of the character don't change. This is mostly done for areas that will deform later after rigging examples being, arms, neck, and knees. But the number of polygons and how high and low they need to depend on where the model will be used for example, when it comes to games, it is much better and optimal to have more triangles however if the model is needed for films and such, then it will have a higher number of polygons and thus will need to have more quads.

Every key area like around the mouth, next to the eyes and the forehead needs to have poles when rerouting which will help with the edge flow. Every pole has five edges coming out of it. 

For a better understanding, we approached the workshop materials and tried our hand at retopology

 When I first started on retopologising the above model, I started off with really small faces because I added too many edges from the very beginning. In the end I very soon realised that instead of trying to lessen the poly count, I added way too many edge loops and thus increased the number faces as it is seen in the above pictures. It defeated the whole purpose of retopologising which was to maintain the original shape but also lessen the poly count. There was so many areas where I didn't need to add more edges. Even the edge flow could have been better like for example around the nose, the edge flow could have been more rounder instead of just straight lines. It is better to follow the flow of the original topology to maintain the finer details like around the mouth, eyes and nose.

Learning from my previous attempt, this time I made sure to lessen the poly count and follow the edge flow of the original topology. I started off with wider faces and slowly added more edges to capture the finer details like the belly button and the chest and it is already looking much better than the previous one with also lesser poly count.